Ultrasonic devices and methods for ablating and removing obstructive matter from anatomical passageways and blood vessels

ABSTRACT

Disclosed are methods and devices for removing obstructive matter from anatomical passageways, including the removal of obstructive matter from the cerebral vasculature, prostatic obstructions from the urinary tract and/or obstructive matter from the fallopian tubes.

RELATED APPLICATION AND INCORPORATION BY REFERENCE

[0001] This patent application is a continuation-in-part of co-pendingU.S. patent application Ser. No. 07/640,190 filed Jan. 11, 1991 entitledULTRASONIC ANGIOPLASTY DEVICE INCORPORATING IMPROVED TRANSMISSION MEMBERAND ABLATION PROBE, the entirety of which is expressly incorporatedherein by reference.

[0002] Also, applicant expressly incorporates herein by reference theentirety of U.S. Pat. No. 5,267,954 entitled ULTRASOUND CATHETER FORREMOVING OBSTRUCTIONS FROM TUBULAR ANATOMICAL STRUCTURES SUCH AS BLOODVESSELS, issued Dec. 7, 1993.

FIELD OF THE INVENTION

[0003] The present invention pertains generally to medical equipmentand, more particularly, to ultrasonic devices and methods for removingobstructive matter from anatomical passageways, including the removal ofobstructive matter from the cerebral vasculature, prostate tissue fromthe urinary tract and/or obstructive matter from the fallopian tubes.

BACKGROUND OF THE INVENTION

[0004] The prior art has included various ultrasonically vibratedsurgical and ablative instruments for treating obstructive disorders ofblood vessels and other anatomical passageways or cavities.

[0005] The prior art devices which, purportedly utilize ultrasonicenergy, alone or in conjunction with other treatment modalities, totreat obstructions within blood vessels or other anatomical structuresof the body include those described in U.S. Pat. Nos. 3,433,226 (Boyd),3,823,717 (Pohlman, et al.), 4,808,153 (Parisi), 4,936,281 (Stasz),3,565,062 (Kuris), 4,924,863 (Sterzer), 4,870,953 (Don Michael, et al.),4,920,954 (Alliger, et al.), and 5,100,423 (Fearnot), 4,136,700(Broadwin), 4,192,294 (Vasilevsky), 4,750,448 (Wuchinich), 4,750,902(Wuchinich), 4,765,332 (Fischell), 4,808,153 (Parisi), 4,832,023(Murphy-Chutorian), 4,867,141 (Nakada), 4,870,953 (Don Michael),4,877,033 (Seitz), 4,886,061 (Fischell), 4,922,902 (Wuchinich),4,936,281 (Stasz), 4,974,581 (Wiksell), 4,989,588 (Kubota), 5,058,570(Idemoto), 5,069,664 (Guess), 5,149,319 (Unger), 5,151,084 (Khek),5,154,723 (Kubota), 5,156,143 (Bocquett), 5,163,421 (Bernstein),5,163,433 (Kagawa), as well as foreign publications nos. WO87-05739(Cooper), WO89-06515 (Bernstein, et al.), WO90-0130 (Sonic NeedleCorp.), EP316789 (Don Michael, et al.), DE3,821,836 (Schubert),DE2,438,648 (Pohlman), GB 1,531,659 (Gekhman, et al.), EP 342448(Bakelite), EP 293472 (Bakelite), and EP 209468 (Sarl).

[0006] Although the prior art has included numerous devices forultrasonic treatment of intracorporeal obstructions, there remains aneed in the art for the development of new and improved ultrasonicdevices having improved or differing capabilities for specific bloodvessels or regions of the body, such as the intracranial andextracranial vessels of the cerebral vasculature and/or the tubes andducts of the genitourinary tracts of the male and female.

SUMMARY OF THE INVENTION

[0007] The present invention provides methods for ultrasonicallytreating obstructions of anatomical passageways of the mammalian bodywith concomitant infusion of a fluid (e.g., saline solution) in a mannerwhich will dilate or fluidically expand the surrounding anatomicalstructure so as to facilitate passage of a catheter through theobstructed region of the anatomical structure. Methodologies inaccordance with this embodiment of the invention are particularly usefulin treating intravascular obstructions as well as obstructions of themale or female urogenital tract, including, but not limited toobstructions of the fallopian tubes and prostatic obstructions of themale urethra.

[0008] Further in accordance with the invention, there are providedmethods for ultrasonically treating obstructions within anatomicalpassageways of the mammalian body while concomitantly aspirating andremoving matter from the anatomical passageway so as to prevent escapeof solid particles or other matter created or released by the ultrasonictreatment process. In accordance with this embodiment of the invention,there are provided methodologies which are particularly applicable inthe ultrasonic treatment of obstructions within intracranial andextracranial cerebral blood vessels which supply blood to the mammalianbrain.

[0009] Further in accordance with the invention, there is provided afirst embodiment of an ultrasound treatment system incorporating anultrasound delivery catheter having one or more fluid infusion lumensfor infusing fluid through the catheter, to effect fluidic dilation ofthe anatomical structure wherein the obstruction is located.

[0010] Still further in accordance with the invention, there is provideda second embodiment of an ultrasound treatment system incorporating anultrasound delivery catheter having at least one aspiration lumenextending longitudinally through the catheter to aspirate and removeparticles or other debris from the anatomical structure wherein theobstruction is located.

[0011] Further objects and advantages of the invention will becomeapparent to those skilled in the art upon reading and understanding thefollowing detailed description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 is a perspective view of a first embodiment of anultrasonic system of the present invention for removing obstructionsfrom genitourinary pathways or other anatomical structures of the body.

[0013]FIG. 2 is an enlarged perspective view of a first embodiment of adistal catheter tip which may be incorporated in the system of FIG. 1.

[0014]FIG. 3 is a longitudinal sectional view through line 3-3 of FIG.2.

[0015]FIG. 4 is a cross-sectional view through line 4-4 of FIG. 3.

[0016]FIG. 5 is an enlarged perspective view of a second embodiment of acatheter tip which may be incorporated into the ultrasound system ofFIG. 1.

[0017]FIG. 6 is a longitudinal sectional view through line 6-6 of FIG.5.

[0018]FIG. 7 is a cross-sectional view through line 7-7 of FIG. 6.

[0019]FIG. 8 is a perspective view of a second embodiment of anultrasound treatment system of the present invention.

[0020]FIG. 9 is an enlarged perspective view of a distal catheter tipwhich may be incorporated into the ultrasound system of FIG. 8.

[0021]FIG. 10 is a longitudinal sectional view through line 10-10 ofFIG. 9.

[0022]FIG. 11 is a cross-sectional view through line 11-11 of FIG. 10.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The following detailed description and the accompanying areprovided for purposes of describing and illustrating presently preferredembodiments of the invention and are not intended to cover everypossible embodiment or configuration of the invention, nor are theyintended to limit the scope of the accompanying claims in any way.

[0024] With references to the drawings, FIGS. 1-7 are directed to afirst embodiment of the invention preferably useable to dilate and treatobstructive disorders of various anatomical passageways, including theurethra and/or fallopian tubes. FIGS. 8-11 are directed to a secondembodiment of the invention preferably useable to effect a) ultrasonicablation of obstructive matter and b) aspiration of the reduced ormorseled matter from the treatment site, such as a cerebral blood vesselor other passageway of the body wherein prompt aspiration or removal ofany solid matter is desired.

[0025] i. Elements and Components of the First Embodiment

[0026] A first embodiment of an ultrasound treatment system 10 of thepresent invention, shown in FIG. 1, comprises an electrical signalgenerator 12 (e.g., Model UAG-1110, Baxter Healthcare Corporation,Cardiovascular Group, Interventional Cardiology Division, Irvine,Calif.) connected by way of cable 13 to an ultrasound transducer 14(e.g., Model UAT-1000, Baxter Healthcare Corporation, Irvine, Calif.)operable to convert the electrical signal from the signal generator 12,into ultrasonic vibration. An elongate ultrasound catheter 16 is coupledto the ultrasound transducer 14 to transmit ultrasonic vibration fromthe transducer 14 to a desired treatment location adjacent the distalend of the catheter 16.

[0027] The catheter 16 component of the first embodiment of theultrasound treatment system 10 may comprise an elongate flexiblecatheter body 18 formed of pliable material and an elongate ultrasoundtransmission wire or member 20 which extends longitudinally through thecatheter body 18. The ultrasound transmission wire or member 20 extendsproximally through a proximal connector assembly 22 whereby the proximalend of the ultrasound transmission member 20 may be coupled or attachedto the ultrasound generating horn of the ultrasound transducer 14. Thedistal end of the ultrasound transmission member 22 is coupled orattached to a distal head member 30 at the distal end of the catheter16.

[0028] The structure and configuration of the proximal connectorassembly 22 of the first embodiment may be the same as that describedand shown in FIG. 10 of U.S. Pat. No. 5,267,954 (Nita), the entirety ofsuch patent being hereby expressly incorporated herein by reference.

[0029] A fluid infusion sidearm 24 extends from proximal connectorassembly 22 and is fluidly communicative with a hollow bore extendingthrough at least a distal portion of the proximal connector assembly 22and into an elongate hollow infusion fluid lumen 26 extending throughthe catheter body 18. A source 28 of pressurized or pumped liquid (e.g.,0.9% NaCl solution) is connected to the fluid infusion sidearm 24 topermit infusion of fluid through the bore of the proximal connectorassembly 22 and through the elongate lumen 26 of the catheter body 18. Adistal head member 30, is mounted on the distal end of the catheter body18. Such distal head member may be of any suitable configuration,including the blunt horizontal faced configuration 30 a shown in FIGS.2-3 and the bullet-like configuration 30 b shown in FIGS. 5-6. In anycase, the distal head member 30 will be provided with one or more fluidoutflow apertures 34 which are fluidly communicative with the fluidlumen 26 of the catheter body 18 to permit irrigation fluid to flow outof the distal head 30 of the catheter 16.

[0030] In the blunt distal head embodiment 30 a shown in FIGS. 2-3, theconfiguration of the distal head member 30 is such that there isprovided a frontal portion 36 having an outer diameter substantiallyequal to the outer diameter of the catheter body 18, and a rear portion38 having an outer diameter substantially equal to the inner diameter atthe distal head of the catheter lumen 26 by such configuration, the rearportion 38 of the distal head member 30 a may be inserted into thedistal end opening of the lumen 26 of catheter body 18 and securedthereto by frictional engagement, mechanical engagement, adhesive, heatsealing or other suitable means. The outer surface of the frontalportion 36 of the distal head member 30 a is thus rendered substantiallycontinuous and in smooth transition with the outer surface of theadjacent catheter body 18. The distal head member 30 a has a centralfluid passageway 32 formed therein, separate and apart from theguidewire passageway 40 which extends longitudinally through the lowerportion of the distal head member 30 a. Such central fluid passageway 32a opens into ancillary passageways 42, said ancillary passageways 42terminating laterally in the multiple fluid outflow apertures 34 formedin the sides of the distal head member 30 a. By such arrangement, fluidinfused through the lumen 26 of the catheter body 18 will enter thecentral fluid passageway 32 a, of the distal head member, 30 a and willsubsequently pass outwardly through the lateral fluid passageways 42 andout of the fluid outflow apertures 34. This may be accomplished while aguidewire (phantom lines) remains inserted into guidewire passageway 40,thereby substantially blocking fluid outflow through guidewirepassageway 40.

[0031] The rate of fluid outflow through outflow apertures 34 may becontrolled to effect any desired degree of irrigation and/or fluidicdilation of a surrounding anatomical structure (e.g., fallopian tube,ureter, duct, blood vessel, etc. . . . )

[0032] The alternative distal head configuration 30 b shown in FIGS. 5-7provides a distal head member 30 b having a frontal portion 36 b and arear portion 38 b. Said frontal portion 36 b having an outer diametersubstantially equal to the outer diameter of the adjacent catheter body18. Said-rear portion 38 b has an outer diameter substantially equal tothe inner diameter of the distal end of the catheter lumen 26. By suchconfiguration, the rear portion 38 b of the distal head member 30 b maybe inserted into the distal end of the catheter lumen 26 a and securedthereto by frictional engagement, mechanical engagement, heat sealing,chemical adhesive, or any other suitable means. When so constructed, thelateral outer surface of the distal head member 30 b is continuous, andsubstantially flush with the adjacent outer surface of the catheter body18, as shown. The alternative distal head member 30 b shown in FIGS. 5-7also differs from the distal head member 30 a shown in FIGS. 2-4 in thatthe guidewire passageway 40 b serves as the central fluid passageway ofthe distal head 30 b, as well as serving as the guidewire passagewaythrough which a guidewire may pass longitudinally through the distalhead member 30 b (see guidewire shown in phantom lines).

[0033] Fluid outflow passageways 42 b pass fluid laterally outward fromthe central guidewire lumen fluid passageway 40 b and lead to multiplefluid outflow apertures 34 b. Thus, when the guidewire (phantom lines)has been removed or retracted so as not to block fluid entry into theguidewire passage lumen/central fluid passageway 40 b,irrigation/dilation/coolant fluid may be infused through the lumen 26 ofthe catheter body 18, through the guidewire passageway/central fluidpassageway 40 b and subsequently outward through the lateral fluidpassageways 42 b and lateral fluid outflow apertures 34 b, as well asthrough the frontal guidewire passageway opening 40 b. The flow rate andvolume of fluid so infused may be controlled to effect any desireddegree of irrigation or dilation of a surrounding anatomical structure(e.g., fallopian tube, ureter, blood vessel or other anatomicalpassageway).

[0034] ii. Preferred Modes of Operation of the First Embodiment

[0035] The ultrasound system 10 of the first embodiment shown in FIGS.1-7 may be utilized for ultrasonic-treatment of various obstructivedisorders of the mammalian body wherein it is desirable to effectconcomitant fluid irrigation or fluid dilation of the anatomicalstructure whereat the distal end of the catheter 18 is positioned.

[0036] Examples of procedures wherein the ultrasound system 10 of thefirst embodiment may be employed include the ultrasonic ablation ofatherosclerotic plaque, thrombus or other obstructive matter within thelumen(s) of mammalian blood vessel(s). Also, as described more fully inthe examples set forth herebelow, the ultrasound system 10 of the firstembodiment may be utilized to effect dilation and/or removal ofobstructive matter (e.g., scar tissue, tumors, congenitally aberranttissue, etc. . . . ) which obstruct tubular passageways of the bodyincluding the ducts and passageway of the urogenital tract (e.g.,urethra, ureter, fallopian tubes).

EXAMPLE 1

[0037] In a first example, an ultrasound system 10 of the firstembodiment of the present invention may be utilized to treatobstructions of the fallopian tubes of a female human being.

[0038] Fallopian tube obstructions are known to occur due to theformation of scar tissue within the lumens of the fallopian tubesfollowing the occurrence of fallopian tube infections, such as chlamydiainfections.

[0039] In treating such blockage of the fallopian tubes, a standardguidewire having an outer diameter of approximately 0.14÷0.25 inch isinserted transvaginally and advanced, with radiographic and/orendoscopic guidance, into the obstructed fallopian tube to a point wherethe distal end of the guidewire 50 is situated adjacent the offendingfallopian tube obstruction. After the guidewire has been positioned, theproximal end of the guidewire 50 is inserted into the distal guidewirepassageway 40 of the catheter 18 and the catheter 18 is advanced overthe guidewire, using standard catheter advancement technique, to a pointwhere the distal head 30 of the catheter 18 has been advanced to aposition adjacent the obstruction to be treated. During such advancementof the catheter, the proximal end of the guidewire 50 will emerge out ofthe guidewire sidearm 52 of the proximal connector assembly 22 so as torender the proximal portion of the guidewire freely accessible to theoperator for subsequent manipulation, extraction or exchange of theguidewire 50, if desired.

[0040] The pressurized fluid source or pump 28 is then utilized to passa flow of irrigation/dilation fluid, such as 0.9% NaCl solution or otherphysiologically compatible liquid, through line 56 and into sidearm 24of proximal end connector assembly 22. The fluid so infused will thenpass, in the distal direction, through the internal bore of the proximalconnector assembly 22, through the lumen 26 of catheter 18 and out ofthe fluid outflow apertures 34 of the distal head 30 of the catheterdevice 16.

[0041] The flow rate of irrigation/dilation fluid out of outflowapertures 34 may be adjusted and controlled so as to provide acontrolled degree of a) fluid-induced dilation of the fallopian tubelumen immediately adjacent the obstruction to be treated and/or b)impingement of fluid against the obstructing scar tissue or othermatter.

[0042] Thereafter, the signal generator 22 may be energized bydepression of on/off foot pedal 11, thereby sending an electrical signalthrough line 13 to ultrasound transducer 14. Such electrical signal isconverted to ultrasonic vibration by ultrasound transducer 14 and theultrasonic vibration is passed, via proximal connector assembly 22, intothe ultrasound transmission wire or member 20, thereby causingultrasonic vibration of the distal head 30 of the catheter 16.

[0043] With continued infusion of the irrigation/dilation fluid, thecatheter 16 may be advanced, or otherwise moved back and forth, suchthat the ultrasonic vibration of the distal head 30 of the catheter 16will effect morcellation or reduction of the obstructive matter. Suchmorcellation or reduction of the obstructive matter by the ultrasonicvibration of the distal head 30 may be effected by direct contact of thevibrating distal head 30 against the obstructive matter and/or bycavitation effect created as a result of the ultrasonically vibratingdistal head 30 in the fluid environment created by the controlledinfusion of the infusion/dilation fluid adjacent the obstructive lesionto be treated.

[0044] In some cases, it may be desirable to initially employ a firstcatheter 16 having a distal head 30 designed for initial dilation of thesurrounding fallopian tube lumen and impingement of the irrigation fluidagainst the offending lesion, and to subsequently utilize one or moreadditional embodiments of the catheter 16 having different designs ofthe distal head 30 so as to effect differing degrees of fluidimpingement against the offending lesion and/or fluidic dilation of thesurrounding luminal wall of the fallopian tube, during differing stagesof the procedure. For example, in some procedures it may be desirable toutilize three(3) separate catheter devices 16, as follows: CATHETER 1Small size Distal head having one or (OD = .5-1.2 more fluid outflow mm)apertures in frontal surface of tip to direct irrigation/dilation fluidinto direct impingement with obstructive matter. CATHETER 2 Medium sizeDistal head having fluid (OD = 1.2-2.0 outflow apertures in mm) frontalsurface of tip and around the lateral sides of tip so as tosimultaneously direct irrigation/dilation fluid in a) a forwarddirection so as to impinge against the obstructive matter and b) inlateral directions so as to exert external dilatory pressure against thesurrounding tube wall. CATHETER 3 Large size Distal head having no (OD =2.0-3.5 fluid outflow apertures mm) in front surface of tip and multiplefluid outflow apertures around lateral sides of tip to exert lateraldilatory pressure against the surrounding tube only.

[0045] In addition to effecting ultrasonic ablation or breakdown of theobstructive matter, the ultrasonic vibration of the distal head 30 ofthe catheter 16 may also cause relaxation of smooth muscle and resultantdilation of the fallopian tube, thereby permitting the catheter 16 to beadvanced back and forth through the previously obstructed region of thefallopian tube.

[0046] In this example, it is preferable that the ultrasonic vibrationof the distal catheter tip 30 be of an optimized frequency and wave formmodulation to effect the desired ablation of the obstruction forinducing smooth muscle relaxation and resultant dilation of theobstructed fallopian tube. one or more inflatable dilation balloonsmounted on the ultrasound catheter device 16 or mounted on a separateballoon catheter may be utilized in conjunction with the ultrasoundcatheter 16, to effect dilation and opening of the obstructed region ofthe fallopian tube.

[0047] After the procedure has been completed and the patency of theobstructed fallopian tube restored, the catheter 16 may be extracted andremoved.

EXAMPLE 2

[0048] In a second example, the ultrasound system 10 of the firstembodiment of the present invention may be utilized to treatobstructions of the male urethra resulting from benign prostatichypertrophy or other prostate enlargement.

[0049] In this example, the catheter device 16 of the first embodimentis inserted, with or without the assistance of a pre-inserted guidewire50, into the male urethra. The catheter 16 is then advanced to a pointwhere the distal head 30 of the catheter 16 is positioned adjacent theobstructing prostatic tissue.

[0050] A pressurized fluid source or pump 28 may be utilized to pump orotherwise expel fluid through tube 54, through sidearm 24, through thelongitudinal bore of the proximal connector assembly 22, through thelumen 26 of catheter 16 and out of the distal fluid outflow apertures34. The flow rate and quantity of the irrigation/dilation fluid beinginfused may be specifically adjusted and/or controlled so as to effectthe desired degrees of a) impingement of the fluid against theobstruction and/or b) fluidic dilation of the surrounding anatomicalstructures (e.g., the urethra).

[0051] Concomitant with the infusion of the irrigation/dilation fluid,signal generator 12 may be energized by depression of on/off foot pedal11, thereby sending an electrical signal through line 13 to ultrasoundtransducer 14. Ultrasound transducer 14 will convert the electricalsignal to ultrasonic vibration and, via proximal connector assembly 22,will pass such ultrasound vibration through ultrasound transmissionmember 20 to the distal head 30 of the catheter 16. Ultrasonic vibrationfrom the catheter tip may thereby result in a) relaxation and dilationof the smooth muscle of the urethra and/or b) ultrasonic ablation ormorselling of the obstruction. For smooth muscle relaxation thepreferred ultrasound frequency is 20 kz to 1MHz. For morselling orablating the obstructing prostate tissue, the preferred ultrasoundfrequency is 20 kz to 100 MHz.

[0052] As described above in Example 1, it may also be desirable toutilize two or more separate catheters 16 having distal heads 30 ofdiffering design, with different positions and configurations of thefluid outflow apertures 34, to facilitate optimal performance of variousphases of the procedure.

[0053] After the prostatic obstruction of the urethra has beenultrasonically ablated and/or dilated so as to restore patency andurinary flow through the urethra, the catheter 16 may be extracted andremoved.

[0054] The foregoing Examples 1 and 2 are intended to illustrate certainspecific intended applications of the ultrasound system 10 of the firstembodiment of the invention, and are not intended to provide acomprehensive discussion of all possible ablative or dilative procedureswherein the ultrasound system 10 may be employed.

[0055] iii. Elements and Components of the Second Embodiment

[0056] FIGS. 8-11 of the drawings are directed to a second embodiment ofan ultrasound system 10 a of the present invention. As shown, suchsecond embodiment ultrasound system 10 a generally comprises a signalgenerator 12 a, an ultrasound transducer 14 a and an elongate catheter16 a, having a proximal connector assembly 22 a positioned on theproximal end thereof for coupling the catheter 16 a to the ultrasoundtransducer 14 a.

[0057] The proximal connector assembly 22 a of the second embodimentultrasound system 10 a may be constructed and configured substantiallythe same as that described hereabove and in incorporated U.S. Pat. No.5,267,954 (Nita), however it will be appreciated that in accordance withthe showing of the second embodiment in FIG. 8 of this patentapplication such ultrasound connector assembly 22 a will include anadditional suction or aspiration sidearm 60 and a separate suction oraspiration tube or secondary lumen (not shown) within the hollow bore ofthe connector assembly 22 a and which is continuous with and fluidicallyconnected to an aspiration lumen or tube member to which extendslongitudinally through the catheter body 18 a for withdrawal oraspiration of debris.

[0058] The catheter 16 a preferably comprises an elongate flexiblecatheter sheath having an ultrasound transmission member or wire 20 aextending longitudinally therethrough. The proximal end of theultrasound transmission member or wire 20 a extends proximally throughthe proximal connector assembly 22 a and is thereby coupleable orconnectable to the ultrasound transducer 14 a. The distal end of theultrasound transmission member wire 20 a is coupled or connected to thedistal head member 30 c of the catheter 16 a so as to transmitultrasonic vibration into the distal head member 30 c.

[0059] The catheter 16 a of the second embodiment shown in FIGS. 8-11 isa “monorail” type of catheter having a guidewire passage lumen 51extending only through a distal portion of the catheter body 18 a. Inthe embodiment shown, the guidewire passage lumen 51 comprises a tubewhich extends from the distal guidewire passage aperture 40 c formed inthe distal end of the distal head member 30 c to a sidewall guidewirepassage aperture 41 c formed in the sidewall of the catheter body 18 a,at a location such as that shown in FIG. 8. By such “monorail”arrangement, the proximal end of a guidewire may be passed into distalguidewire aperture 40 c and advanced through guidewire lumen 51 so as tosubsequently exit the catheter body 18 a through sidewall aperture 41 c.The proximal portion of the guidewire 50 may reside outboard of thecatheter body 18a as is typical of “monorail” type catheters.

[0060] It will be appreciated that an over-the-wire embodiment may alsobe designed incorporating a guidewire tube or lumen which extendslongitudinally through the entire catheter body 18 a, with a separateguidewire passage sidearm formed in the proximal connector 22 a, in amanner similar or the same as that shown in FIG. 1 with respect to thefirst embodiment described hereabove.

[0061] An aspiration tube member 70 extends longitudinally through theinternal bore 26 a of the catheter body 68 a and longitudinally througha separate dedicated bore formed in the distal head member 30 c asshown. The distal end of the aspiration tube member 70 is flush with thedistal or frontal face of the distal head member The proximal end of theaspiration tube member 70 is fluidly connected or continuous withaspiration sidearm 60, thereby forming a continuous dedicated aspirationchannel through the catheter 16 a. Aspiration pump 62 is connected toaspiration sidearm 60 by way of tube 64. Debris collection vessel 66 isconnected to aspiration pump 62 by tube 68. By such arrangement,aspiration pump 62 may be utilized to withdraw or aspirate debris fromthe area adjacent the distal end of the catheter, in a proximaldirection, through aspiration tube member 70 and into debris collectionvessel 66.

[0062] iv. Preferred Modes of Operation of the Second Embodiment

[0063] With reference to FIGS. 8-11, the ultrasound system 10 a of thesecond embodiment may be operated to effect ultrasonic dilation,morselling, pulverization or other treatment of obstructive matterwithin a vessel or passageway of a mammalian body. Concomitant with orseparate from the ultrasonic treatment, the system 10 a may also beutilized to a) infuse irrigation/coolant/dilation fluid through thecatheter 16 a and out of the distal end thereof and b) aspirate debris,fluid or other matter, in a proximal direction, through the catheter 16a and into the debris collection vessel 66.

[0064] The aspiration and debris collection capability of the system 10a of the second embodiment is particularly useful in applicationswherein it is desired to promptly remove or suction away any particlesof solid matter which may be created or liberated as a result of theultrasonic treatment process. The ability to aspirate and suction awaydebris or particles of solid matter is particularly important invascular applications, wherein it is desirable to avoid any embolizationor migration of solid matter into the organ or tissue, which is perfusedby the blood vessel wherein the treatment is being applied. For example,in procedures wherein ultrasound is utilized to treat or ablateobstructions of the extracranial and/or intracranial blood vessels whichprofuse the brain, it is highly desirable to prevent the passage of anysolid particulate matter into the brain, as such may result in highlyundesirable sequelae such as iatrogenic stroke or embolization ofsmaller blood vessels which may be situated downstream from the site ofthe treatment procedure. In such cerebrovascular applications, theability to promptly aspirate any solid particles which may have beencreated or released by the ultrasonic procedure is useful to preventsuch solid particles from resulting in untoward embolization of thebrain.

[0065] Arterial blood flow to the brain is provided mainly by four(4)large extracranial arteries, two common carotid arteries and two(2)vertebral arteries, which feed smaller intracranial arteries. The two(2)vertebral arteries originate from the right and left subclavianarteries, respectively, and pass into the cranium through the foramenmagnum. The vertebral arteries give off branches to form the anteriorspinal artery, the posterior and inferior cerebellar arteries, and thebasilar artery. The common carotid arteries bifurcate into the internaland external carotid arteries. The internal carotid arteries pass intothe cranium and give off the ophthalmic, posterior communicating andanterior choroidal arteries. The internal carotid arteries also form, byterminal bifurcation, the anterior and middle cerebral arteries.

[0066] Obstructions may form in any of the intracranial or extracranialcerebral arteries, including all of those described hereabove. Suchobstructions may result from atherosclerotic narrowing of thosearteries, or may come about due to a thromboembolic event, such as themigration of a blood clot into the cerebral circulation from the heartor some other location.

[0067] The clinical significance and severity of symptoms resulting fromobstruction of the cerebral blood vessels may vary, depending on theorigin or type of obstruction, the location of the obstruction and otherfactors. The degrees of resultant ischemia may vary, ranging from a) a“transient ischemic attack” (TIA) wherein a transient focal loss ofneurologic function occurs, to b) a “partial non-progressing stroke”(PNS) producing minor persistent neurologic disability to c) a“completed stroke” (CS) producing major permanent neurologic disability.

[0068] The following are examples of applications wherein the ultrasoundsystem 10 a of the second embodiment of the present invention isutilized to treat obstructions of the cerebral blood vessels so as totreat or prevent conditions such as TIA, PNS or CS as describedhereabove.

EXAMPLE 3

[0069] In this example, the second embodiment of the ultrasound system10 a shown in FIGS. 8-11 is utilized to treat an atheroscleroticobstruction of the extracranial internal carotid artery of a humanbeing.

[0070] Initially, a guidewire 50 is percutaneously inserted into aperipheral artery and advanced, under radiologic guidance, to a positionwhereat the distal end of the guidewire 50 is positioned in the internalcarotid artery immediately upstream of the obstruction to be treated.

[0071] The proximal end of the guidewire is passed into the distalguidewire aperture 40 c of the catheter device 16 a and the catheterdevice 16 a is advanced over the guidewire, with the proximal end of theguidewire 50 emerging from the sidewall guidewire aperture 41 c as thecatheter 16 a is further advanced to a point where the distal head 30 cof the catheter 16 a is positioned adjacent the obstruction to betreated.

[0072] The guidewire 50 is then fully or partially withdrawn into thetubular guidewire lumen 51 of the catheter device 16 a.

[0073] Foot pedal 11 a is depressed to energize signal generator 12 asuch that an electrical signal emitted by signal generator 12 a passesthrough line 13 a to ultrasound transducer 14 a. Ultrasound fromultrasound transducer 14 a passes, via proximal connector assembly 22 a,into the proximal end of the ultrasound transmission member 20 a andtravels through ultrasound transmission member 20 a to distal headmember 40 c, thereby causing ultrasonic vibration of distal head member40 c.

[0074] Concomitant with the delivery of ultrasound to the distal headmember 40 c, a flow of 0.9% Nacl solution is pumped via pump 28 a,through the catheter lumen 26 a. Such flow of saline solution throughthe catheter lumen 26 a accomplishes the dual function of a) bathing andcooling the ultrasound transmission member 29 a to prevent excessiveheat build-up as a result of the ultrasonic vibration thereof and b)providing a flow of irrigation/dilation fluid into central fluidpassageway 32 c, through secondary fluid passageway 42 c and out offluid outflow apertures 34 c.

[0075] Also, concomitant with the delivery of ultrasound to the distalhead 30 c and the infusion of irrigation/dilation fluid out of fluidoutflow apertures 34 c, a suction is applied, via suction pump 62,through line 64 to aspiration sidearm 60, thereby drawing negativepressure on the lumen of aspiration tube 70 so as to draw particulatematter or other debris adjacent the distal tip of the catheter 16 a intothe distal aspiration port 72, through aspiration tube 72 and intodebris collection vessel 66.

[0076] The flow of saline solution out of the fluid outflow apertures 34c and the intake of matter into aspiration port 72 may be adjusted andcontrolled, by adjustment and control of infusion pump 28 a andaspiration pump 62, such that the two(2) flow rates are substantiallyequal to one another, such that saline solution flowing out of the fluidoutflow apertures 34 c will circulate adjacent the distal head memberand be subsequently withdrawn into the aspiration port 72 a and throughaspiration tube 70 into debris container 66. By such equilibration ofthe infusion outflow and aspiration outflow rate, a continuous fluidturnover may be affected to accomplish prompt lavage and removal of anyparticulate matter or other debris generated adjacent the distal head 30c of the catheter device 16 a.

[0077] The catheter 16 a may be proximally advanced and/or moved backand forth so as to effectively treat the obstructive lesion, therebyimproving blood flow and restoring patency to the lumen of the internalcarotid artery wherein the treatment is applied.

[0078] When desired, the aspiration pump 62 may be turned off and aquantity of radiographic contrast medium may be passed into infusionsidearm 58, through catheter lumen 26 a and out of distal fluid outflowapertures 34 c to radiographically visualize the area of the obstructionfor purposes of determining whether the treatment has effectivelyablated or opened the obstruction.

[0079] After successful treatment and opening of the obstruction hasbeen radiographically verified, the catheter device 16 a may bewithdrawn and removed.

EXAMPLE 4

[0080] In this example, the second embodiment of the ultrasound system10 a shown in FIGS. 8-11 is utilized to ultrasonically treat anobstruction of the intracranial middle cerebral artery of a human being.

[0081] Initially, a guidewire 50 is percutaneously inserted into aperipheral artery and advanced, under radiographic guidance, to aposition whereat the distal end of the guidewire 50 is positioned withinthe cerebral artery, immediately upflow of the obstruction to betreated.

[0082] Thereafter, the proximal end of the guidewire 50 is inserted intothe guidewire entry aperture 40 c in the distal head 30 c of thecatheter device 16 a and the catheter device 16 a is advanced in theproximal direction, with the proximal end of the guidewire 50 emergingoutwardly through sidewall guidewire aperture 51. The advancement of thecatheter 16 a is continued until the distal head 30 c is positioned inthe middle cerebral artery immediately adjacent the obstruction to betreated.

[0083] Thereafter, the guidewire 50 is fully or partially withdrawn, atleast to a point whereat the distal tip of the guidewire is within theguidewire tube 70 internal of the body of catheter 16 a.

[0084] Foot pedal 11 a is depressed to energize signal generator 28 a,thereby sending an electrical signal through line 13 a to ultrasoundtransducer 14 a. Ultrasound from transducer 14 a passes, via proximalconnector assembly 22 a, into ultrasound transmission member 20 a and iscarried by said ultrasound transmission member 20 a to the distal head30 c of the catheter device 16 a, thereby causing the distal head 30 cto vibrate ultrasonically within the desired frequency range.

[0085] Relaxation of the vascular smooth muscle within the middlecerebral artery results from the ultrasonic vibration within theabove-stated frequency range, thereby causing some dilation of themiddle cerebral artery in the region of the obstruction to be treated.

[0086] Concomitant with the delivery of ultrasound to the distal headmember 40 c, a flow of 0.9% NaCl solution is pumped via pump 28 a,through the catheter lumen 26 a. Such flow of saline solution throughthe catheter lumen 26 a accomplishes the dual function of a) bathing andcooling the ultrasound transmission member 20 a to prevent excessiveheat build-up as a result of the ultrasonic vibration thereof and b)providing a flow of irrigation/dilation fluid into central fluidpassageway 32 c, through secondary fluid passageway 42 c and out offluid outflow apertures 34 c.

[0087] Also, concomitant with the delivery of ultrasound to the distalhead 30 c and the infusion of irrigation/dilation fluid out of fluidoutflow apertures 34 c, a suction is applied, via suction pump 62,through line 64 to aspiration sidearm 60, thereby drawing negativepressure on the lumen of aspiration tube 70 so as to draw particulatematter or other debris adjacent the distal tip of the catheter 16 a intothe distal aspiration port 72, through aspiration tube 72 and intodebris collection vessel 66.

[0088] The flow of saline solution out of the fluid outflow apertures 34c and the intake of matter into aspiration port 72 may be adjusted andcontrolled, by adjustment and control of infusion pump 28 a andaspiration pump 62, such that the two(2) flow rates are substantiallyequal to one another, such that saline solution flowing out of the fluidoutflow apertures 34 c will circulate adjacent the distal head memberand be subsequently withdrawn into the aspiration port 72 a and throughaspiration tube 70 into debris container 66. By such equilibration ofthe infusion outflow and aspiration outflow rate, a continuous fluidturnover may be affected to accomplish prompt lavage and removal of anyparticulate matter or other debris generated adjacent the distal head 30c of the catheter device 16 a.

[0089] The catheter 16 a may be proximally advanced and/or moved backand forth so as to effectively treat the obstructive lesion, therebyimproving blood flow and restoring patency to the lumen of the internalcarotid artery wherein the treatment is applied.

[0090] When desired, the aspiration pump 62 may be turned off and aquantity of radiographic contrast medium may be passed into infusionsidearm 58, through catheter lumen 26 a and out of distal fluid outflowapertures 34 c to radiographically visualize the area of the obstructionfor purposes of determining whether the treatment has effectivelyablated or opened the obstruction.

[0091] After successful treatment and opening of the obstruction hasbeen radiographically verified, the catheter device 16 a may bewithdrawn and removed.

[0092] It will be appreciated that the foregoing drawings, descriptionsof preferred embodiments, and examples serve to describe and illustratespecific embodiments of the invention but do not describe or encompassevery possible embodiment of the invention which may be constructed orutilized. Accordingly, it is intended that the above-set-forthdescription, drawings and examples be broadly construed so as toencompass all foreseeable additions, modifications and alterations whichthose of skill in the art would be inclined to make.

What is claimed is:
 1. A method of treating an obstruction of a tubularanatomical passageway of the urogenital tract, said method comprisingthe steps of: a) providing an ultrasound catheter having a proximal end,and a distal end, said catheter comprising: i. an elongate flexiblecatheter body having a proximal end, a distal end, and a longitudinalaxis extending longitudinally therethrough; ii. at least one ultrasoundtransmission member extending longitudinally through said catheter body,and coupleable to an ultrasound source, said ultrasound transmissionmember having a distal end which is substantially coterminous with thedistal end of said catheter body; iii. At least one fluid infusion lumenextending longitudinally through said catheter body and opening throughat east one fluid outflow aperture formed at the distal end of saidcatheter body. b) inserting said catheter, distal end first, into theurogenital tract and advancing said catheter to a point where the distalend of said catheter is adjacent the obstruction to be retreated; c)coupling said ultrasound transmission member to an ultrasound source andutilizing said ultrasound source to pass ultrasound through saidultrasound transmission member to the distal end of said catheter; d)infusing a liquid infusate through said infusion lumen and out of saiddistal outflow aperture.
 2. The method of claim 1 wherein step b)further comprises: providing a guidewire having a proximal end and adistal end; initially inserting said guidewire, distal end first, intothe urogenital tract and advancing said guidewire to a point where thedistal end of said guidewire is adjacent the obstruction to be treated;subsequently advancing said catheter over said guidewire to a pointwhere the distal end of said catheter is adjacent the obstruction to betreated.
 3. The method of claim 1 utilized to treat an obstruction of afallopian tube, wherein step b) of said method further comprises:inserting said catheter device, distal end first, into said obstructedfallopian tube and advancing said catheter to a poin where the distalend of said catheter is adjacent the fallopian tube obstruction to betreated.
 4. The method of claim 1 for treating a prostatic obstructionof the urethra, wherein step b) of said method further comprises:inserting said catheter device, distal end first, into the urethra andadvancing said catheter to a point where the distal end of said catheteris adjacent the prostatic obstruction to be treated.
 5. The method ofclaim 1 wherein said at least one fluid outflow aperture of saidcatheter device comprises a plurality of lateral outflow aperturespositioned to expel fluid in lateral directions generally perpendicularto the longitudinal axis of said elongate catheter body and wherein stepd) further comprises: infusing a liquid infusate through said infusionlumen and out of said distal outflow apertures so as to cause radialdilation of the tubular anatomical passageway in which said catheter isinserted.
 6. The method of claim 1 wherein said fluid outflow apertureof said ultrasound catheter device is configured and positioned to expelfluid in the distal direction, parallel to the longitudinal axis of saidcatheter and wherein step d) further comprises: infusing said fluid at arate which will cause said fluid to be expelled in the distal directionparallel to the longitudinal axis of said catheter and into impingementwith said obstruction.
 7. The method of claim 1 wherein step d) furthercomprises infusing said liquid infusate through said infusion lumen suchthat said liquid infusate comes in contact with said ultrasoundtransmission member so as to remove excess heat from said ultrasoundtransmission member and subsequently passes out of said distal outflowaperture.
 8. The method claim 1 wherein step c) further comprises:utilizing said ultrasound source to pass ultrasound within the frequencyrange of 20 kHz to 1 MHz through said ultrasound transmission member tothe distal end of said catheter to thereby cause ultrasound inducedsmooth muscle relaxation and resultant dilation of the anatomicalpassageway.
 9. A method of ultrasonically treating an obstruction of ablood vessel, said method comprising the steps of: a) providing anultrasound catheter having a proximal end and a distal end, saidcatheter comprising: i) an elongate flexible catheter body having aproximal end, a distal end and a longitudinal axis extendinglongitudinally therethrough; ii) at least one ultrasound transmissionmember extending longitudinally through said catheter body andcoupleable to an ultrasound source, said ultrasound transmission memberhaving a distal end which is substantially coterminous with the distalend of said catheter body; iii) at least one fluid infusion lumenextending longitudinally through said catheter body and opening throughat least one fluid outflow aperture formed at the distal end of saidcatheter body; iv) at least one aspiration lumen extendinglongitudinally through said catheter body and opening through at leastone aspiration port formed in the distal-most centimeter of saidcatheter body; b) inserting said catheter device, distal end first, intothe vasculature and advancing said catheter to a point where the distalend of said catheter is adjacent the obstruction to be treated; c)coupling said ultrasound transmission member to an ultrasound source andutilizing said ultrasound source to pass ultrasound through saidultrasound transmission member to the distal end of said catheter; d)infusing a liquid infusate through said infusion lumen and out of saiddistal outflow aperture; e) applying suction to said aspiration lumen todraw matter into said distal aspiration port and through said aspirationlumen of said catheter.
 10. The method of claim 9 utilized to treat acerebral vascular obstruction, wherein step b) of said method furthercomprises: inserting said catheter, distal end first, into thevasculature and advancing said catheter to a point where the distal endof said catheter is positioned in an intracranial or extracranialcerebral blood vessel, adjacent the obstruction to be treated.
 11. Themethod of claim 10 wherein the obstruction to be treated is in a carotidartery and wherein the distal head of said catheter is positioned withinsaid carotid artery adjacent the obstruction to be treated.
 12. Themethod of claim 10 wherein the obstruction to be treated is in avertebral artery and wherein step b) further comprises positioning thedistal end of said catheter within said vertebral artery adjacent theobstruction to be treated.
 13. The method of claim 10 wherein theobstruction to be treated is in a basilar artery and wherein step b)further comprises positioning the distal end of said catheter withinsaid basilar artery adjacent the obstruction to be treated.
 14. Themethod of claim 10 wherein the obstruction to be treated is in aanterior cerebral artery and wherein step b) further comprisespositioning the distal end of said catheter within said anteriorcerebral artery adjacent the obstruction to be treated
 15. The method ofclaim 10 wherein the obstruction to be treated is in a middle cerebralartery and wherein step b) further comprises positioning the distal endof said catheter within said middle cerebral artery adjacent theobstruction to be treated.
 16. The method of claim 10 wherein theobstruction to be treated is in a posterior cerebral artery and whereinstep b) further comprises positioning the distal end of said catheterwithin said posterior cerebral artery adjacent the obstruction to betreated.
 17. The method of claim 10 wherein said method furthercomprises the step of: maintaining the rate of infusion through saidinfusion lumen and maintaining the rate of aspiration through saidaspiration lumen such that said rates of infusion and aspiration aresubstantially equivalent.
 18. The method of claim 9 wherein step d)further comprises infusing said liquid infusate through said infusionlumen such that said liquid infusate comes in contact with saidultrasound transmission member so as to remove excess heat from saidultrasound transmission member and subsequently passes out of saiddistal outflow aperture.
 19. The method claim 9 wherein step c) furthercomprises: utilizing said ultrasound source to pass ultrasound withinthe frefuency range of 20 kHz to 1 MHz through said ultrasoundtransmission member to the distal end of said catheter to thereby causeultrasound induced smooth muscle relaxation and resultant dilation ofthe anatomical passageway.
 20. An ultrasound catheter device fordelivering ultrasound from an external ultrasound source to a locationinside a mammalian body, said device comprising: a) a tubular catheterbody having a proximal end, a distal end, at least one lumen extendinglongitudinally therethrough and a longitudinal axis; b) a distal headmember comprising a plug at least partially inserted into the distal endof the lumen of the catheter body, said distal head member having atleast one fluid passageway extending therethrough and terminating in atleast one fluid outflow aperture said fluid passageway being configuredto carry fluid from said catheter lumen, through said fluid passagewayand out of said fluid outflow aperture; c) a proximal connector assemblyon the proximal end of said catheter body, said proximal connectorassembly having at least one bore extending longitudinally therethroughin fluid connection with the lumen of said catheter body, and at leastone fluid infusion port to permit infusion of fluid; d) an ultrasoundtransmission member having a proximal end and a distal end, saidultrasound transmission member extending longitudinally through thelumen of said catheter body and into the bore of said proximal connectorassembly, the distal end of said ultrasound transmission member being incontact with said distal head member and the proximal end of saidultrasound transmission member being coupleable, by way of said proximalconnector assembly, to said external ultrasound source; e) said catheterdevice being thereby constructed to concomitantly deliver: i) ultrasonicvibration from said ultrasound source to the distal head member of saidcatheter; and ii) a flow of infusion/dilation fluid through saidcatheter body and out of said at least one fluid outflow aperture. 21.The catheter device of claim 20 further comprising: an aspirationpassageway formed in said distal head member and terminating in at leastone aspiration port on the outer surface of said distal head member; atleast one aspiration tube extending longitudinally through said catheterbody and having a distal end opening through an aspiration port formedin said distal head member, said aspiration tube having a proximal endwhich is connectable to a suction source so as to draw matter into saidaspiration port and through said aspiration tube, in the proximaldirection.
 22. The catheter device of claim 20 wherein said distal headmember has a lateral sidewall and a frontal surface and wherein said atleast one distal outflow aperture comprises: a plurality of aperturesformed at spaced locations about the lateral surface of said distal headmember to expel fluid in outward directions generally perpendicular tothe longitudinal axis of said catheter body.
 23. The device of claim 20wherein said at least one fluid outflow aperture comprises a pluralityof fluid outflow apertures formed at spaced locations about said distalhead member such that expulsion of fluid out of said outflow apertureswill cause radial dilation of a surrounding anatomical passageway. 24.The vice of claim 20 wherein said at least one fluid outflow aperturecomprises: at least one bore extending longitudinally through saiddistal head member such that expulsion of fluid from said outflowaperture will flow forward from said distal head member in a directiongenerally parallel to the longitudinal axis of said catheter body. 25.The device of claim 20 wherein said distal head member comprises agenerally cylindrical plug having a cylindrical lateral outer surfacewhich is substantially continuous with the adjacent outer surface ofsaid catheter body.
 26. The device of claim 20 wherein said distal headmember has a frontal surface of blunt radiused configuration.
 27. Thedevice of claim 20 said distal head member has a central fluidpassageway extending longitudinally therein to and fluidly communicativewith the lumen of said catheter, said central fluid passageway leadingto a plurality of secondary fluid passageways which lead to a pluralityof fluid outflow apertures, respectively, so as to carry infusion fluidfrom the lumen of said catheter, through said distal head member and outof said plurality of fluid outflow apertures.
 28. The device of claim 20wherein said catheter is an over-the-wire type of catheter which furthercomprises: a guidewire lumen extending longitudinally through saidcatheter and having a guidewire passageway extending longitudinallythrough said distal head and opening through the distal surface thereof.29. The device of claim 20 wherein said catheter is a monorail type ofcatheter which further comprises: a monorail guidewire passage lumenextending through a distal portion of said catheter, from a distalguidewire aperture formed in the distal surface of said distal headmember to a sidewall guidewire passage aperture formed in the sidewallof said catheter at a location between the proximal and distal ends ofsaid catheter.